1. Technical Field
The present invention relates to an improved process for the continuous production of potassium formate by the reaction of gaseous monomeric formaldehyde with potassium hydroxide. Particularly, the invention relates to a straightforward method wherein potassium formate production and removal of excess reactant(s) is realized very efficiently from monomeric gaseous formaldehyde present in the reactor outlet gas in formaldehyde production plants.
2. Description of Related Art
Potassium formate solution is used mainly as deicer, drilling mud, and/or in the production of flaked or granular potassium formate by appropriate methods. The flaked and granular potassium formate inturn is used in the fields mentioned above as well as an additive to animal food.
There has been conventionally provided several methods for the production of potassium formate. One production method thereof is the reaction between formic acid and potassium hydroxide solution, but since formic acid is expensive this method is not economical. Another method is by reacting carbon monoxide and potassium hydroxide solution, which results in some drawbacks such as high reaction temperatures and pressures and low reaction rates. Still another method is the production of pentaerythritol where potassium formate is the byproduct when potassium hydroxide is used as the catalyst.
Furthermore, there was also provided several approaches in industrial scale, for example, wherein a reaction between formaldehyde solution and potassium hydroxide solution, substantially in liquid forms, is carried out for the production of potassium formate. The basic disadvantages thereof are high energy consumption for the evaporation of water coming with formaldehyde solution; not too fast reaction rate compared to the present invention; being a batch reaction; the storage and transportation problems of methanol obtained after the distillation of the product solution; and the difficulties in elimination and consumption of the large amount of water contaminated with methanol obtained during the purification of the product solution.